The prevalence of adequate blood pressure control was investigated in 614 patients (mean age 60 +/- 16 years) with systemic hypertension followed in a university cardiology or general medicine clinic. Systemic hypertension was adequately controlled in 46 of 122 patients (38%) who had to pay for their medications (self-pay or Medicare patients) versus 342 of 492 patients (70%) who received their medications at minimal or no cost because they were on Medicaid or had private insurance (p <0.001).